Re: [kvm-unit-tests PATCH v3 08/10] arm64: pmu: count EL2 cycles

[Eric Auger <eric.auger@redhat.com>]

On 9/25/25 4:19 PM, Joey Gouly wrote:
> Count EL2 cycles if that's the EL kvm-unit-tests is running at!
>
> Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  arm/pmu.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/arm/pmu.c b/arm/pmu.c
> index 2dc0822b..e6c0f05b 100644
> --- a/arm/pmu.c
> +++ b/arm/pmu.c
> @@ -121,6 +121,8 @@ static struct pmu pmu;
>  #define PMINTENCLR   __ACCESS_CP15(c9, 0, c14, 2)
>  #define PMCCNTR64    __ACCESS_CP15_64(0, c9)
>  
> +#define PMCCFILTR_EL0_DEFAULT	0
> +
>  static inline uint32_t get_id_dfr0(void) { return read_sysreg(ID_DFR0); }
>  static inline uint32_t get_pmcr(void) { return read_sysreg(PMCR); }
>  static inline void set_pmcr(uint32_t v) { write_sysreg(v, PMCR); }
> @@ -206,6 +208,9 @@ static void test_overflow_interrupt(bool overflow_at_64bits) {}
>  #define ID_DFR0_PMU_V3_8_5	0b0110
>  #define ID_DFR0_PMU_IMPDEF	0b1111
>  
> +#define PMCCFILTR_EL0_NSH	BIT(27)
> +#define PMCCFILTR_EL0_DEFAULT	(current_level() == CurrentEL_EL2 ? PMCCFILTR_EL0_NSH : 0)
> +
>  static inline uint32_t get_id_aa64dfr0(void) { return read_sysreg(id_aa64dfr0_el1); }
>  static inline uint32_t get_pmcr(void) { return read_sysreg(pmcr_el0); }
>  static inline void set_pmcr(uint32_t v) { write_sysreg(v, pmcr_el0); }
> @@ -246,8 +251,7 @@ static inline void precise_instrs_loop(int loop, uint32_t pmcr)
>  #define PMCNTENSET_EL0 sys_reg(3, 3, 9, 12, 1)
>  #define PMCNTENCLR_EL0 sys_reg(3, 3, 9, 12, 2)
>  
> -#define PMEVTYPER_EXCLUDE_EL1 BIT(31)
> -#define PMEVTYPER_EXCLUDE_EL0 BIT(30)
> +#define PMEVTYPER_EXCLUDE_EL0 BIT(30) | (current_level() == CurrentEL_EL2 ? BIT(27) : 0)
>  
>  static bool is_event_supported(uint32_t n, bool warn)
>  {
> @@ -1063,7 +1067,8 @@ static bool check_cycles_increase(void)
>  	/* init before event access, this test only cares about cycle count */
>  	pmu_reset();
>  	set_pmcntenset(1 << PMU_CYCLE_IDX);
> -	set_pmccfiltr(0); /* count cycles in EL0, EL1, but not EL2 */
> +
> +	set_pmccfiltr(PMCCFILTR_EL0_DEFAULT);
>  
>  	set_pmcr(get_pmcr() | PMU_PMCR_LC | PMU_PMCR_C | PMU_PMCR_E);
>  	isb();
> @@ -1118,7 +1123,7 @@ static bool check_cpi(int cpi)
>  	/* init before event access, this test only cares about cycle count */
>  	pmu_reset();
>  	set_pmcntenset(1 << PMU_CYCLE_IDX);
> -	set_pmccfiltr(0); /* count cycles in EL0, EL1, but not EL2 */
> +	set_pmccfiltr(PMCCFILTR_EL0_DEFAULT);
>  
>  	if (cpi > 0)
>  		printf("Checking for CPI=%d.\n", cpi);